1. Field of the Invention
The present invention relates to a mobile communication network apparatus, a base station, and a mobile station, and in particular to a mobile communication network apparatus, a base station, and a mobile station which transfer an incoming call for the mobile station to a predetermined transfer destination.
In recent years, a rapid widespread of mobile stations such as mobile telephones followed by advances in mobile communication technology has been fundamentally changing economies and societies. In such a mobile communication, it is important to construct e.g. an incoming call transfer system which transfers an incoming call for a mobile station to another receiving station, in consideration of users' convenience.
2. Description of the Related Art
In recent years, there is a move to regulate calls of mobile telephones or the like which annoy others in public places such as a hospital, concert hall, bullet train, train, and bus.
Based on such a background, a prior art mobile communication system disclosed has a mobile station, a base station, a control center for managing a plurality of base stations, means for detecting whether or not the mobile station is in an incoming call prohibited place, and announcement prohibiting means for prohibiting an announcement of incoming call ringing to the mobile station when the mobile station is in the incoming call prohibited place according to the detection result.
Also, there is a prior art technology that the mobile communication system has message recording/reproducing means for recording a message from a transmitting source and for reproducing the message in response to a request of a mobile station user, in order to reduce disadvantage of losing an opportunity to obtain information due to an incoming call prohibition (see e.g. patent document 1).
This mobile communication system is for recording/reproducing the message in response to the request of the mobile station user, and is not for making a direct conversation of the transmitting source with the mobile station user.
There is a prior art mobile communication system and its transfer destination setting method of a mobile unit comprising a mobile telephone exchange as well as a fixed telephone and a radio wave transmitting device located in an assembly room or the like, respectively connected to a public communication network, a plurality of mobile units having a radio telephone function managed by the mobile telephone exchange, wherein the radio wave transmitting device is provided with signal generating/transmitting means for generating a transfer destination setting reception signal of a predetermined radio frequency indicating that the radio wave transmitting device can accept a transfer destination to be radio-transmitted continuously, request signal transmitting means for calling the mobile telephone exchange which receives a first response signal including a telephone number from a mobile unit responsive to the transfer setting reception signal with a predetermined first channel and for transmitting a transfer destination setting request signal together with the telephone number of the mobile unit which has transmitted the first response signal and a telephone number of the fixed telephone of a preset transfer destination, location confirming means for transmitting a location confirming signal from a predetermined second channel together with the telephone number of the mobile unit for the mobile unit having transmitted the first response signal after transmitting the transfer destination setting request signal and for receiving a second response signal together with the telephone number of the mobile unit for the location confirming signal with a predetermined third channel and, releasing means for transmitting a release signal for requesting a transfer destination setting release for the mobile unit to the mobile telephone exchange in the absence of the second response signal responsive to the location confirming signal, whereby an incoming call for the mobile unit which has moved to an area such as an assembly room which is outside of a mobile communication area is automatically transferred (see e.g. patent document 2).
Namely, without troubling a user on a mobile terminal side, a transfer destination to a fixed telephone is automatically set even if a mobile terminal moves out of a mobile communication area, and this transfer setting is automatically released if the mobile terminal returns to the area.
[Patent Document 1]                Japanese Patent Application Laid-open No. 7-87568 (page 2, FIG. 1)        
[Patent Document 2]                Japanese Patent Application Laid-open No. 2001-298776 (page 2, FIG. 1)        
However, this mobile communication system and the transfer destination setting method of the mobile unit (mobile station) are for performing an incoming call transfer for the mobile unit which has moved out of a service area of the mobile communication network, and require a radio wave transmitting device for detecting that the mobile unit has entered a predetermined area outside the service area of the mobile communication network. Also, it is required for the radio wave transmitting device to transmit, to a mobile telephone exchange, a transfer destination setting request signal including telephone numbers of the mobile unit and of a transfer destination fixed telephone preset.